All posts by Bryce

Biggest Full Moon plus Meteors!

This weekend the moon is at Perigee which means it will be at its closest point to the Earth ~and~ there will be a meteor shower caused by the debris from Halley’s comet. This sounds like a great deal, I mean, HUGE full moon and a meteor shower both!?! But really, the huge full moon will make it hard to see the meteors. You should still be able to see one every couple minutes or so.

Along with the regular little pin streak meteors there will be some giant fireballs. These chunks of space rock hit the earth’s atmosphere going 139,000 mph and disintegrate at about 50 miles up. Last night there were seven events.

The eta Aquarid meteor shower is going to peak before sunrise on May 5. So get out there and look at the moon and meteors.

There’s an All Sky camera network in the US that records black and white videos of meteor fireballs. It’s run by NASA and some volunteers. You can see fisheye video camera footage of the fireballs at http://fireballs.ndc.nasa.gov/ If you click on a date, you can see the meteors that were filmed on that date. Each ‘Event’ has a timestamp and video clips from the cameras that were able to record the event. There are a total of seven cameras, and all the events on May 4, of which there were 11, were caught by two cameras.

All Sky Cam Fireball Meteor

You can even listen to to meteors. Well, to their radar echoes anyhow. Check out Spaceweather Radio.

The moon at perigee is 14% bigger and 30% brighter than the other full moons of 2012.

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Birch Lake (foreground), one of the "jewels" in Montana's Jewel Basin Hiking Area. It is backdropped by Squaw and Crater Lakes.

Scientists: Walking in the woods scares game

Researchers at the University of Calgary have been studying the effect human trail walkers have on wildlife in Canada’s parks, and they have found….wait for it…that people scare the animals away from trails.

So while this seems like something we all knew, actually that’s a gross over simplification of what the researchers did. In truth, they discovered the thresholds levels of human activity that cause elk and wolves to change their behavior. And they observed that wolves and elk react differently to people walking on the trails.

By using GPS collars on wolves and elk, and sensors on trails, the scientists found that one hiker an hour kept the animals 50m?away from the trail habitat. Two hikers per hour kept the wolves 400m away and the elk began to use the area near the trail as a refuge from predation.

As human traffic on the trails increased to over 2 people per hour, both species stayed 400m away from the trail, resulting in loss of habitat. That’s about a half mile width, or .73 kilometers?wide.? Over the length of?a trail this would add up to some significant square miles. On a busy 5 mile trail, 2.5 square miles of habitat would be lost due to human presence.

So imagine yourself affecting an area a half mile wide as you hunt. A quarter mile all around you.

They didn’t do research on low level traffic like hunting, where you may be the only human who has walked along this certain ridge all year. But if you are in an area where other people hunt every day you might expect that the critters are avoiding the area. The elk are 1200 feet away, so maybe you need to get off the trail by 400m.

Low level trail traffic must not keep elk and deer away from the trail as much. Otherwise we’d never see any game. The study did mention that wolves like to use trails (“linear features”)?when they aren’t often used be humans.

Here’s a link to the original research:

Discussion section of Human Activity Differentially Redistributes Large Mammals in the Canadian Rockies National Parks

Oufitter backs switching to copper ammo

Since researchers at Craighead Beringia South have been able to document a rise in lead levels in ravens and eagles during hunting season, it’s gotten a little easier for outfitters and environmentalists to see eye-to-eye, at least on the issue of lead poisioning.

The Jackson Hole News and Guide reports that Kelly outfitter B.J. Hill said recently that he supports the switch from lead bullets to copper bullets. He stated that 95% of his clients have already made the switch to copper bullets on their own.

?Copper is a better-technology bullet to begin with,? he said, in part because there?s less fragmenting than with lead. ?It?s a better bullet for harvesting elk, [and] it doesn?t have the poisoning effect.?

Hill is a board member of the Wyoming Outfitters and Guides Association and a member of Jackson Hole Outfitters.

Researchers from Craighead Beringia South have been doing field work capturing eagles and ravens and sampling their blood, which is then tested for lead levels. They have found that lead levels rise about two weeks after hunting season starts, and then drop off about two weeks after hunting season ends. This last hunting season, the researchers passed out 194 boxes of copper ammo to the hunters who had permits to hunt on the refuge and found that the lead levels in the birds’ blood did not rise as high this year.

When a lead bullet strikes an animal such as an elk, there are a lot of lead fragments.

Lead Fragments in xray image of deer carcass
Lead fragments in a carcass show up clearly in x-ray image

So when the birds feed on the gut pile, they ingest lead.

This is a big problem for California Condors too. The Beringia researchers say that “Each year, more condors are clinically treated for lead poisoning.”